Extensive experimentation in pavement construction has been conducted using steel fiber reinforced concrete (SFRC). Although SFRC has demonstrated outstanding mechanical properties, its commercial application has ben limited because of high cost. Cost savings could be realised for paving projects constructed with the emerging roller compacted concrete (RCC) technology. In particular, pavement thickness reduction due to the inclusion of fibers in RCC can allow single-lift construction where two lifts of unreinforced concrete would be required. Alternatively, for two or more lifts, SFRC can be confined to the most stressed layer(s). This paper presents compression and split tension results of laboratory cylinders and field cores reinforced with different types of steel fiber in various percentages. The concrete matrix contained fly ash, either class F (used as a filler) or class C (used as a binder). Fiber inclusion disturbed the consolidation of laboratory specimens, whereas field cores did not indicate any loss of density or compressive strength. Post-cracking characteristics were greatly enhanced by fibers with ultimate strength and toughness indexes derived from stress-strain curves for split tension. Sample design calculations compare the preliminary pavement thickness of unreinforced and fiber reinforced RCC with cost estimates for each.
Samenvatting